Eew...
I'd have to say lolfish. If you haven't seen it, I strongly don't advise viewing it yourself.
The blue waffle thing brought back memories of the stupid kids of the class. They looked it up on Google Images and covered up the screen with their hand because it was so disturbing. Even though they wanted to see it. WTF. The teacher had a program to actively view our desktop. He never caught them. Not once.
Ew... I've never seen it myself, but this kid at my Karate class actually almost threw up talking about it. I'm glad I've never looked up Blue Waffle....
As for scaries thing on the net, any well founded creepypasta or urban legend that doesn't include 666 popping up randomly. Yes, it is evil, it makes my hairs stand on edge, but not in an OMG sort of way, but more of a, "SCREW THAT" way.Yes, I am Christian, so yeah.
As for things that have actually made me go sleep in my parent's beds (literally) they'd be these:
Suicide Mouse (Scared the heck out of me when I first read it. I thought it would pop up on my T.V which randmoly turns on at times).
The Grifter (Never seen it myself, but I don't dare have the audacity to watch a single millisecond of it).
Dead Bart (Same as Suicide Mouse)
Squidward''s Suicide (Same as above)
Lost Silver didn't exactly scare me, but it did creep me out. Pokemon creepypastas don't have the sting to make me not be able to sleep at night.... except for the Lavender Town tune and whitehand.gif and Buried alive man whom I played poker with last night. The Lavender Town tune creeped me out because the whole, "Kids cried when they couldn't play it and killed themselves", which reminded me of the original reason why my parents never let me play pokemon as a little kid. All those 3 creepypastas were enough to not let me pick up HG for 2 days in a row.
Snow on Mt. Silver was creepy, but I actually like rereading it.